API Monitoring

Catch API degradation before it becomes an outage

NotiLens monitors API error rates, latency trends, throughput silence, and broken webhook flows — alerting you when performance degrades, errors spike, or traffic disappears entirely.

Works with your API infrastructure
AWS API Gateway
Cloudflare
Datadog
Sentry
Postman
Webhook

API failures don't always look like failures

A 5% error rate. A 200ms latency increase. A gradual throughput drop. These are the degradation patterns that slip through threshold-based monitoring and compound into real incidents.

API latency spiked silently

Your checkout endpoint's p95 latency drifted from 180ms to 1,400ms over 90 minutes. No single response crossed your timeout threshold. But conversion rate dropped 30% before anyone noticed.

Endpoint returning errors silently

A schema migration caused POST /orders to return 422s for specific request shapes. 15% of orders were failing. Your uptime monitor showed 100% — because it only checks GET /health.

Traffic disappeared overnight

Your API received zero requests for 34 minutes. No one noticed because it was 3am. But your SLA required 99.9% uptime — and that silence counted against it whether or not anyone was watching.

Monitoring that understands API behavior

NotiLens goes beyond simple uptime checks — it watches your API's behavioral patterns and alerts on trends, anomalies, and silence.

API error rate detection

NotiLens tracks error counts per endpoint and computes a rolling baseline. Get alerted the moment a specific endpoint's error rate exceeds its normal pattern — not just a global threshold.

Latency trend monitoring

Send response time events per request. NotiLens spots when latency is trending up and can flag gradual drift before it compounds into a user-facing slowdown that threshold alerts miss entirely.

Throughput silence alerts

Define a minimum expected request volume per window. If traffic drops to zero or below your threshold, NotiLens alerts you before the silence triggers an SLA breach or goes unnoticed until morning.

Broken webhook flow detection

Define two-step flows like webhook.received → order.acknowledged. If the second event never fires in your window, NotiLens alerts you — before a silent drop in your event processing pipeline causes data loss.

Metric drift detection

Launched May 2026, drift detection catches gradual baseline shifts over time — like response times that creep up 50ms every day. These are invisible to threshold-based alerts but compound into real user-facing slowdowns.

Acknowledgement (ACK)

Critical error rate alerts repeat every 5 minutes until someone on your team acknowledges them. A checkout endpoint failing at 3am won't go unnoticed until your support queue explodes at 9am.

What NotiLens sends your team

Endpoint-specific alerts with baselines and context — so you know exactly where to look and what to expect when you get there.

NotiLens Live Feed — API Monitoring
API response time spiked to 4.2s on /api/checkout — baseline 180ms
Topic: api-performance • Degradation alert • 2 min ago
Warning
POST /api/checkout error rate 18% — 18x above baseline
Topic: api-errors • Rate anomaly • 11 min ago
Critical
Webhook received — order.acknowledged never fired — 7 events dropped
Topic: webhook-flow • Broken flow • webhook.received → order.acknowledged • 34 min ago
Critical
No API calls in 2 hours — normally 400/hr at this time
Topic: api-throughput • Silence threshold exceeded • 4 min ago
Warning

Zero traffic is not the same as healthy traffic.

When your API goes quiet, traditional uptime monitors don't fire — because the endpoint is still responding. NotiLens detects when expected traffic disappears and alerts you immediately, regardless of what your health check returns.

How is this different from Pingdom or Better Uptime? +
Pingdom checks if your server responds. NotiLens watches what your API actually does — event rates, error rates, silence on specific endpoints, broken request flows. Your server can respond 200 while your API is silently failing on a specific route. That gap is exactly what NotiLens is built to catch.
Can I monitor specific endpoints rather than just uptime? +
Yes. Forward request events from your gateway or middleware. NotiLens tracks error rates, response times, and event volumes per endpoint — and alerts when any metric deviates from baseline. Each endpoint can be its own topic with independent thresholds and subscriber lists.
What is metric drift detection? +
Launched May 2026, drift detection catches gradual baseline shifts over time — like response times that creep up 50ms every day. These are invisible to threshold-based alerts but compound into real user-facing slowdowns. NotiLens flags the trend before it becomes an outage, giving you lead time to diagnose before users notice.
Do I need to install an agent on my server? +
No. Forward events from your existing API gateway, NGINX logs, or middleware using webhooks or the SDK. No agent process to manage, no server access required. If you already use Cloudflare, AWS API Gateway, or Datadog, you can forward events from those tools directly to NotiLens without touching your application code.

Monitor every API endpoint that matters

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